I have an LG LWHD1200R window unit. Recently it began to cycle through its different modes all on its own. Compressor and fan both work great, and it may stay on the selected mode without any problem for days, but then all of a sudden it will start to change modes from cool, to power save, to fan, to dry, and back again to cool all on its own. Sometimes it will jump just to the next mode, sometimes it will cycle through them real fast for an hour or so, and then settle down.

I should add that the control buttons on the unit are temperamental. Sometimes they work, sometimes they don't. The remote always works fine.

I'm thinking the problem is with one of the PCB control boards. But there are 2 and I can't figure out which controls what.

I tried looking for the manual for the unit, but the links to it seem to be dead.

Well, I read the manual and I still wasn't certain which of the boards might be the problem, so I took the unit apart last night.

I inspected both boards, looking for any corrosion, blown transistors, a bad microswitch, and couldn't find anything wrong. (there are a lot of chips in there so one of those could be the problem)

I turned the unit on with the board hanging loose and it kept doing the mode jumping. I reassembled the whole thing and the problem is (as of now) gone!

Weird huh?

In any case (unless someone else has a better suggestion) I will be buying and replacing the control / display PCB. My reasoning is that the board has the mode switch on it, and the problem is bound to come back (as it has before.) It's only about $30 w/shipping from Sears Parts Direct.

Not a bad price, but Sear does not support our forum like our parts affiliates do.Affiliate Disclosure

Sears also do not provide service manuals like we do.

Not sure how Sears is on returning electronic parts, but our parts affiliate RepairClinic.com and AppliancePartsPros.com both have a no hassle 365 day return policy. You can return any part for any reason. Even parts you had installed. So there is no harm in buying and trying.